Hydraulic gravity ram pump

Abstract

A piston type pumping apparatus comprises a vertically oriented cylinder having a top and a bottom with a first aperture. There are first and second passageways for liquid in the cylinder at the top and bottom respectively thereof. A piston is reciprocatingly mounted within the cylinder and has an area against which pressurized fluid acts in the direction of movement of the piston. A hollow piston rod is connected to the piston and extends below the piston and slidably through the first aperture. There is a reload chamber below the cylinder. The piston rod extends slidably into the reload chamber and has a third passageway for liquid communicating thereto. A first one-way valve is located in the third passageway. There is also a fourth passageway that extends from the reload chamber to a source of liquid to be pumped and a second one-way valve therein.

What is claimed is: 
     
         1 . A piston type pumping apparatus configured for pumping a liquid, comprising:
 a vertically oriented cylinder having a top and bottom;   a first passageway for hydraulic fluid adjacent to the bottom of the vertically oriented cylinder;   a second passageway for hydraulic fluid adjacent to the top of the vertically oriented cylinder;   a piston reciprocatingly mounted within the vertically oriented cylinder having a top area against which hydraulic fluid acts in a direction of movement of the piston and a bottom area against which hydraulic fluid acts in the direction of movement of the piston;   a hollow piston rod connected to the piston and mounted within the vertically oriented cylinder, wherein the hollow piston rod comprises a first one-way valve;   a transfer chamber located above the vertically oriented cylinder such that a top portion of the hollow piston rod extends reciprocatingly and sealingly though a first aperture in the top of the vertically oriented cylinder and into the transfer chamber, wherein the first one-way valve is positioned to allow fluid flow from the hollow piston rod into the transfer chamber;   a reload chamber located below the vertically oriented cylinder such that a bottom portion of the vertically oriented cylinder extends receiprocatingly and sealingly through a second aperture in the bottom of the vertically oriented cylinder and into the reload chamber;   a second one-way valve located in the reload chamber, wherein the second one-way valve is positioned to allow fluid flow into the reload chamber from outside the piston type pumping apparatus; and   a discharge chamber located above and in fluid communication with the transfer chamber, wherein the discharge chamber and the transfer chamber are connected by a third one-way valve configured to allow fluid flow from the transfer chamber into the discharge chamber.   
     
     
         2 . The apparatus of  claim 1 , wherein the piston is annular in shape. 
     
     
         3 . The apparatus of  claim 1 , wherein the first one-way valve includes a first valve member, a first valve seat and a first valve passageway, the second one-way valve includes a second valve member, a second valve seat and a second valve passageway, and the third one-way valve includes a third valve member, a third valve seat and a third valve passageway. 
     
     
         4 . The apparatus of  claim 1 , wherein the hollow piston rod is cylindrical in shape. 
     
     
         5 . The apparatus of  claim 1 , wherein the reload chamber is sealingly attached to the cylinder apart from the first aperture. 
     
     
         6 . The apparatus of  claim 1 , wherein the transfer chamber is sealingly attached to the cylinder apart from the second aperture. 
     
     
         7 . The apparatus of  claim 1 , wherein the discharge chamber is sealingly attached to the transfer chamber apart from the third one-way valve. 
     
     
         8 . The apparatus of  claim 1 , wherein a diameter of the cylinder is greater than a diameter of the reload chamber. 
     
     
         9 . The apparatus of  claim 1 , wherein a diameter of the cylinder is greater than a diameter of the transfer chamber. 
     
     
         10 . The apparatus of  claim 1 , wherein a diameter of the hollow piston rod is equal to or less then a diameter of the transfer chamber. 
     
     
         11 . A method for pumping fluid comprising:
 introducing a power fluid into a piston-type pumping apparatus according to  claim 1 , through a first passageway in a vertically oriented cylinder, whereby a piston housed within the vertically oriented cylinder is raised, whereby a piston rod attached to the piston rises upwardly through a first aperture in a transfer chamber, wherein a first one-way valve in the piston rod is closed, whereby liquid is prevented from flowing from the transfer chamber into the piston rod, wherein a second one-way valve is opened to allow liquid flow into the reload chamber from outside the piston-type pumping apparatus, wherein raising the piston rod upwardly into the transfer chamber displaces fluid in the transfer chamber through a third one-way valve into a discharge chamber; and   introducing fluid through a second passageway into the vertically oriented cylinder, whereby the piston in lowered and hydraulic fluid exits the vertically oriented cylinder through the first passageway, wherein the third one-way valve is closed, thereby preventing fluid flow from the discharge chamber into the transfer chamber, wherein the second one-way valve is closed and prevents fluid flow from the reload chamber and the piston rod from exiting the piston-type pumping apparatus, and wherein the first one-way valve is opened to allow fluid to flow from the reload chamber and the hollow piston rod into the transfer chamber.   
     
     
         12 . The method of  claim 11  further comprising priming the reload chamber. 
     
     
         13 . The method of  claim 12 , wherein priming the reload chamber comprises
 filling the reload chamber, the hollow piston rod and the discharge chamber with fluid to be pumped;   placing the piston in its lowermost position adjacent to the bottom of the vertically oriented cylinder; and   closing the first one-way valve, the second one-way valve and the third one-way valve.   
     
     
         14 . The method of  claim 11 , wherein the third one-way valve prevents liquid in the discharge chamber from reentereing the transfer chamber. 
     
     
         15 . The method of  claim 11 , wherein a diameter of the piston rod is less than or equal to a diameter of the reload chamber and a diameter of the transfer chamber, respectively. 
     
     
         16 . The method of  claim 11 , wherein increasing the diameter of the piston rod increases a volume of fluid pumped by the apparatus. 
     
     
         17 . The method of  claim 11 , wherein increasing a surface area of the piston increases force on the piston rod acting on fluid in the transfer chamber.